The Organisation for Security and Co-operation in Europe may send an armed police mission to help conduct elections in conflict-torn eastern Ukraine, if there is agreement on all sides.

OSCE secretary general Lamberto Zannier said his group was ready to send hundreds of policemen, potentially armed, to ensure the vote took place in a secure and safe atmosphere.

"It would be a police operation to help maintain law and order in this area and to help provide a safe environment for the elections to take place," he said in Washington.

As part of an internationally-brokered peace agreement, Ukraine must hold local elections in two eastern regions controlled by Russian-backed rebels, but progress on ending the two-year conflict that has already killed more than 9,300 people has been slow.

Moscow says Ukraine must pass the necessary legislation to conduct the vote and Kiev insists the separatists must first cease all hostilities and pull back weapons and Ukraine must restore control over its border with Russia.

The sides are also at odds over the degree of autonomy that will be granted to the separatist regions and the details of a prisoner exchange and amnesty for the rebels.

Mr Zannier said the mission, requested by Ukrainian president Petro Poroshenko, could work alongside the local police force in the Donetsk and Lugansk regions to prevent criminal activity and help international observers monitor the vote.

The mission would be able to deploy only after both sides fully committed to a ceasefire.

"It is a complicated scenario, but it's certainly something that we can do if, as I say, everybody agrees," Mr Zannier said.

Russia, however, has spoken against such a mission, with foreign minister Sergey Lavrov calling the issue "an artificial problem" and saying unarmed monitors of OSCE would be enough for the vote.

Ukranian ambassador to the US Valeriy Chaly said: "As of today, it is impossible to conduct normal elections.

"Russia will continue playing its game and try to do what it wants to do - for Ukraine to have this cancerous tumour. This position is unacceptable."